Conventionally, a refrigerating cycle apparatus utilizing an expander is known that uses a fluid to be a supercritical state as a refrigerant to improve COP (Coefficient of Performance: energy consumption efficiency) by spraying water over part of the surface of a heat source side heat exchanger or a load side heat exchanger.
For example, there is a refrigerating cycle apparatus, in which a refrigerant circuit is configured by connecting a compressor, a flow path switching means, a heat source side heat exchanger, and a load side heat exchanger, and including a water spray apparatus that sprays water onto the surface of part of a heat source side heat exchanger or part of a load side heat exchanger. It is arranged that water can be sprayed onto part of the heat source side heat exchanger or the load side heat exchanger where a high-pressure refrigerant discharged from the compressor passes. (refer to Patent Literature 1, for example)
When applied to an air conditioning apparatus, the temperature of the refrigerant can be lowered by cooling the refrigerant by spraying water at the outlet of the heat source side heat exchanger in the cooling operation. The performance can be improved by increasing the difference of enthalpy in an evaporator to be a load side heat exchanger.
As another example of the refrigerating cycle apparatus using the expander, some refrigerating cycle apparatus includes water spray means that sprays water to improve the COP.
For example, with the refrigerating cycle apparatus that constitutes a refrigerant circuit by connecting the compressor, the heat source side heat exchanger, the expander, and the load side heat exchanger, the heat source side heat exchanger is disposed outdoors to make outdoor air and the refrigerant to perform heat exchange. On the other hand, the load side heat exchanger is disposed indoors to make indoor air and the refrigerant to perform heat exchange. In the cooling operation in which the heat source side heat exchanger is used as a radiator, water spray means sprays water all over the surface of the heat source side heat exchanger. (Refer to Patent Literature 2)
In the cooling operation, when spraying water on the heat source side heat exchanger that radiates heat on the refrigerant side, water absorbs heat from the refrigerant to evaporate. Accordingly, the heat radiation amount from the refrigerant can be increased for as much as evaporation latent heat of the water, allowing to decrease the enthalpy of the refrigerant transmitted to the load side heat exchanger. Excessive water spray is suppressed by adjusting the water spray amount.